DOUBLE E COMPANY
31Patents
5Active
31Granted
51Portfolio score
Filing activity: Aug 24, 1973 → May 19, 2023 · 1 expiring within 5 years
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4844406A | Blowout preventer | Fixed Constructions | 35 | Expired |
| US4907650A | Wellhead with safety valve for pumping well | Fixed Constructions | 26 | Expired |
| US5246067A | Well leak catcher | Fixed Constructions | 24 | Expired |
| US6223819A | Wellhead for providing structure when utilizing a well pumping system | Fixed Constructions | 24 | Expired |
| US4289294A | Wellhead flow control devices | Mechanical Engineering; Lighting; Heating | 20 | Expired |
| US5044602A | Blowout preventer | Emerging Cross-Sectional Technologies | 15 | Expired |
| US3963250A | Chuck | Emerging Cross-Sectional Technologies | 15 | Expired |
| US3993317A | Core chuck | Emerging Cross-Sectional Technologies | 14 | Expired |
| US4073497A | Care chuck stop assembly | Emerging Cross-Sectional Technologies | 13 | Expired |
| US6716148B1 | Metal-sleeved carbon fiber anilox roller base | Emerging Cross-Sectional Technologies | 13 | Expired |
| US4492346A | Positive retracting mechanical expansible shaft | Performing Operations; Transporting | 12 | Expired |
| US4254920A | Air shaft | Performing Operations; Transporting | 12 | Expired |
| US4193633A | Core chuck | Emerging Cross-Sectional Technologies | 9 | Expired |
| US5690300A | Interlocked core shaft | Performing Operations; Transporting | 9 | Expired |
| US4469288A | Expansible shaft with actuator retaining member and spherical bearing surface | Mechanical Engineering; Lighting; Heating | 9 | Expired |
| US4433814A | Core-engager retainer for an expansible shaft | Performing Operations; Transporting | 8 | Expired |
| US4519620A | Core chuck with resilient rollers | Emerging Cross-Sectional Technologies | 8 | Expired |
| US4155242A | Core tools | Performing Operations; Transporting | 8 | Expired |
| US5915647A | One-piece core plug | Performing Operations; Transporting | 5 | Expired |
| US5878812A | Misaligning wellhead system | Fixed Constructions | 5 | Expired |
| US5435385A | Integrated wellhead tubing string | Fixed Constructions | 5 | Expired |
| US4632468A | Guide for well pump sucker rod | Fixed Constructions | 3 | Expired |
| US6416014B2 | Expandable core plug | Performing Operations; Transporting | 3 | Expired |
| US5797532A | Web edge control system | Performing Operations; Transporting | 2 | Expired |
| US4286791A | Packing assembly for a movable shaft | Mechanical Engineering; Lighting; Heating | 2 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.